android - How to fetch fragment manager without extending the Activity -

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i using libraries build cards, java extends library class have requirement use fragmentmanager in java class tried using inner class getting null pointer exception

if have activity reference: activity.getfragmentmanager()

if have fragment reference: fragment.getfragmentmanager()

they both public methods, you'll need reference either activity or fragment.

also, , though don't recommend it, if have view reference, view.getcontext() method likely activity, might able cast , fragmentmanager way. potentially dangerous, , stop working @ moment if android's implementations change, should know you're doing. passing activity/fragment reference way go.


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